The present invention relates to a structure for fixing a rail to a concrete tie and more particularly adapted to the fixing of the rail to a tie of the "composite" type, ie. formed by two blocks of reinforced concrete interconnected by a steel strut or girder which extends at each end axially into the concrete block.
In ties of this type, the strut is placed on the longitudinal axis of the concrete blocks perpendicular to the axis of the rail and requires disposing the conventional fixing bolts or coach-screws on each side of the axis of symmetry of the tie or providing apertures in the strut for the passage of tightening means. Now, experience has shown that fasteners thus offset result in an increased fatigue of the fasteners of the rail and possibly of the elastically yieldable sole placed under the latter, when the rail deflects and oscillates on the tie upon the passage of wheels thereover.
Further, the apertures formed in the strut weaken the tie and in particular reduce its strength as concerns dynamic shear. The same is true of the vertical and lateral passages formed in the concrete which are essential in systems employing bolts having a hammer head.